Study On The Depth Of Penetration Of Anchors

When ships anchor near the submarine pipelines, anchors may strike submarine pipeline. This threatens the safety of submarine pipelines. With development of offshore exploitation activities, the quantity of submarine pipelines and ships is increasing. Appropriate buried depth will help to reduce the influence of mooring operations. Study on the depth of penetration of anchors can help to provide reference for determining the buried depth of submarine pipelines. Thereby damages caused by anchors will reduce.The thesis analyses the anchor’s movement during anchoring. And it divides anchor’s movement into two parts, one in the water and the other in seabed soil.First, the thesis researches the process in water. It analyzes anchor’s movement and forces acting on the anchor, then it builds calculation model to find out anchor’s velocity when it hits the seabed. By solving the differential equations, it gets the relationship between the anchor’s velocity and its shifting in water. Then the thesis gets anchor’s velocity when it hits the seabed.After that, the thesis researches the process penetrating into seabed soil. It analyzes anchor’s movement and the forces acting on the anchor, then it builds calculation model. The thesis use MATLAB to solve differential equations combined with anchor velocity. Finally the thesis gets the penetration depth of anchors.The thesis designs a GUI program based on the results obtained in the study of penetration depth. Then it calculates several penetration depths, and searches measured penetration values from related articles. Then the thesis makes comparative analysis between the two. Finally it gets a regression equation describing the relationship between penetration depth and anchor’s weight.